The present invention relates to a plain film platform for a projection screen apparatus, an X-ray picture apparatus or the like. More particularly, it relates to a plain film platform for such apparatuses which is arranged vertically and open upwardly for automatic insertion and withdrawal of the films, and is provided with guiding strips extending at least along a vertical side and a lower side and having grooves for insertion and holding a film. Advantageously, a vacuum device is provided for vacuum attraction of film to the surface of the platform.
Plain film platforms of this type are customary in the above mentioned apparatus. In the field of X-ray picture apparatuses and projection screen apparatuses of X-ray pictures, a lot of various film formats are used. It is necessary to use the film platform with a size corresponding to films of maximum provided format, which leads to a material waste.